1. Field of the Invention
The invention relates to a waterproof connector configured to prevent water from penetrating an area in which terminals are housed.
2. Description of the Related Art
The waterproof connector 200 illustrated in FIGS. 13 to 19 is not disclosed in any publication, and not used in public. Accordingly, the waterproof connector 200 does not constitute prior art against the present invention. However, it is helpful for better understanding of the present invention to describe the waterproof connector 200. Thus, the waterproof connector 200 is explained hereinbelow with reference to FIGS. 13 to 19 only for the purpose of better understanding of the present invention. The description of the waterproof connector 200 does not mean that the applicant admits the waterproof connector 200 as prior art.
As illustrated in FIG. 13, the waterproof connector 200 includes a female housing 201 made of an electrically insulating material and formed with a recess 209 being open toward the front of the female housing 201, a front holder 202 fit into the recess 209, a front seal 203 fit into the recess 209, and a plurality of terminals 205 inserted into terminal storage spaces 204 being open at a rear of the female housing 201.
When a male housing 207 including a sealed circuit board 206 is inserted into the recess 209 of the female housing 201, an extension 206a of the sealed circuit board 206 is inserted into a space 208 formed in the female housing 201 and being open to the recess 209, and thereby, an electrically conductive portion formed at a surface of the extension 206a makes partial contact with one of the terminals 205 being exposed to the space 208. Thus, the sealed circuit board 206 and the terminal 205 are electrically connected to each other.
As illustrated in FIGS. 14 to 19, the waterproof connector 200 is designed to include an engagement piece 210 extending from a corner of the front holder 202, and a recess 211 being open to the front of the recess 209 in order to position the front holder 202 at a predetermined position in the recess 209 of the female housing 201. When the front holder 202 is fit into the recess 209, the engagement piece 210 of the front holder 202 is inserted into the recess 211, and thus, the front holder 202 is positioned at a predetermined position in the recess 209 in accordance with later-mentioned two steps.
Specifically, when the front holder 202 is fit into the recess 209 of the female housing 201 in a process of assembling the waterproof connector 200, the front holder 202 is subject to firstly a pre-set condition as illustrated in FIG. 17, and secondly a complete-set condition as illustrated in FIG. 19.
In order to carry out the above-mentioned two steps, as illustrated in FIG. 15, there are formed a first projection 213 and a second projection 214 in the recess 211. The engagement piece 210 is formed at a front end thereof with a projection 212 capable of being engaged with the first and second projections 213 and 214. The first and second projections 213 and 214 are spaced apart from each other in a direction Z (see FIG. 15 in which the first and second projections 213 and 124 downwardly protrude) in which the engagement piece 210 is inserted into the recess 211. The first projection 213 is located downstream relative to the second projection 214 in the direction Z. As illustrated in FIGS. 14 to 16 and 18, the first and second projections 213 and 214 are not aligned in the direction Z, but are aligned in a direction perpendicular to the direction Z.
In the pre-set condition illustrated in FIG. 17, the projection 212 of the engagement piece 210 is engaged with the first projection 213. In the complete-set condition illustrated in FIG. 19, the projection 212 is engaged with the second projection 214.
The waterproof connector 200 is accompanied with a structural limitation that the female connector 201 cannot be designed to include a through-hole through which inside and outside thereof make fluid-communication with each other, because an area in which an electrically conductive portion (not illustrated) of the extension 206a makes contact with the terminal 205 is necessary to be kept waterproof. Accordingly, the recess 211 formed in the female housing 201 has to have a bottom, as illustrated in FIG. 15. That is, a through-hole cannot be formed in place of the recess 211, and the recess 211 has to be dead-end in a direction Z in which the front holder 202 is inserted into the recess 211.
Consequently, in a die (not illustrated) used for molding the female housing 201 with resin, portions for molding the first and second projections 213 and 214 are undercut portions. As a solution to this problem, the first and second projections 213 and 214 were attempted to be formed by forced extraction from a die. However, the first and second projections 213 and 214 were shaved due to the friction generated between a die and themselves when the female housing 201 were separated from a die, resulting in that the projection 212 formed at the engagement piece 210 of the front holder 202 cannot have a sufficient margin with which the projection 212 is engaged with the first and second projections 213 and 214, and accordingly, it was difficult to put the front holder 202 into the above-mentioned pre-set condition.
Furthermore, the waterproof connector 100 is accompanied with a problem in that the waterproof connector 100 is assembled with a poor efficiency, because a plurality of parts such as the front holder 202 and the front seal 203 has to be attached to the female housing 201.
Japanese patent No. 4986807 has suggested a connector including a cover and a sealing unit. However, since the cover and the sealing unit are separate parts from each other, the connector is accompanied with a problem of a poor efficiency with which the connector is assembled.
Japanese Patent Application Publication No. 2004-185918 has suggested a waterproof connector, in which a terminal having been inserted into a housing is engaged only with a lance in the housing. The secondary engagement between the terminal and the housing is not prepared. Thus, the terminal cannot be fully held in a predetermined position, resulting in poor reliability to the connection between the terminal and the housing.
Furthermore, the waterproof connector does not have a function of detecting whether a terminal is completely inserted into a housing, resulting in poor reliability to the insertion of a terminal into a housing.